Improving seedling production for Vitex doniana

Uniform germination is one of the important agronomic requirements for successful domestication of wild-harvested economic plants. In this study we investigated the effects of storage and hydration-dehydration regimes on Vitex doniana seed viability, germination speed and seedling growth and vigour. These effects were tested in a factorial combination of four storage durations (0, 2, 4 and 8 months) and five hydration-dehydration regimes including the control, alternating one hour soaking in tap water with eight hours sun-drying for 3, 7, 14 and 21 days. After two months storage at room temperature, germination percentage was not significantly different from initial germination; seed viability and germination decreased with storage beyond two months. For the first time, germination in V. doniana reached 83%, for seeds stored for two months and then submitted to 21 days of hydration-dehydration cycles. Two months storage combined with hydration-dehydration regimes for 14 or 21 days improved germination speed and seedling growth and vigour. We recommend that fresh seeds be stored for a maximum of two months and stratified by consecutive hydration-dehydration cycles for 14 or 21 days to obtain a homogenous seedling cohort. These results represent an important step towards domesticating V. doniana in West Africa.